daemon to lock files into RAM

 When a system starts paging excessively it may be impossible for the sysadmin
 to login for the purpose of killing the runaway processes (sometimes the
 login program times out due to thrashing). Memlockd allows important system
 files (such as /bin/login, /bin/getty, and the admin shell) to be locked in
 memory so that there will be no delay in accessing executable pages. In my
 tests this can decrease the time required for the administrator to login on a
 thrashing system by a factor of more than 3.